Furnace wall



O. NYGAARD Feb. 1931.

FURNACE WALL Filed Sept. 4, 1928 2 Sheets-Sheet l ES/VENTOR:

ffl-g3 O. NYGAARD Feb. 17, 1931.

" FURNACE WALL. v

Filed Sept. 4, 1928y 2 Sheets-Sheet v12 24T-ro RNE Patented Feliz.` 17, 1931 oscar?. naam, or savage, lassacnusmi'rs FURNACE 'WALL Application mea september 4, 192s. sensi no. 'acssa This invention relates to furnace walls and i is more especially concerned with that type.

of furnace wall in which tubes ar'elembedded and serve to conduct a fluid medium for carvor with engineers, particular y in'pu vler,

ized fuel installations and other furnaces which are operated at high temperatures for long periods of time. In such casesethe cooling of the walls in some manner is -absolutely necessary to prevent their rapid destruction and the accomplishment of this ob]ect by circulating steam or water through pipes embedded in the walls, not only affords a convenient method of controlling the temperature of the wall with a high degree of accuracy, but it is also of advantage 1n transferring excessive heat from the wall to the 2 boiler, where it adds to the efficiency of the installation.

The present invention aims to. lmprove furnace walls of this general type with a view to simplifying their construction, reducln the `first cost, and facilitating the makmg o re airs.

he nature of the invention will be read-l ily understood from the followingl description when read in connection'with t e accompanying drawings, and the novel features will be particularly pointed out 1n the appended claims.

In the drawings;

Fig. 1 is a front elevation of a small section of a furnace wall constructed in accordance with `this invention;

Fig. 2 is a sectional view on the hne 2-2,

Fig. 3 is a sectional view on the line 3 3, o Fi 1;

y Fig. 4 is a perspective view of one of the blocks or bricks used in the wall shown 1n Fi 1' Y igj is a horizontal, sectional view of an individual brick or block, showing the manner in whichit is held or locked to the tubes;

Fig. 6 is a side elevation of the brick shown in Fig. 5; Y

Fig. 7 is a view simllar to Fig. 5 and shows a modified construction;

n Fig. 8 is a side elevation of the brick shown 1n Fig. 7;

gig. 9 isa section on the line 9-9, Fig. 2; an

fFig. 10 is a view'similar to Figs. 5 an'd 7 showmg a further modification.

Referring first to Figs. 1, 2, and 3, the wall there shown comprises a series of pi es or tubes 2,.usually supported in an uprig t position and in parallel relationship. Associated with these tubes are bricks or blocksy 3, arrangedv in vertical rows, the bricks in each row being located end to end. The construction of the individual bricks is best illustrated in Figs. 3 and 4. It will be observed that each brick is of approximately T shape in horizontal section, and has a face portion to lie in front of and protect the front portions of two adjacent tubes and a rear- Ward extension or tongue 4, which projects between adjacent tubes. Considered from a somewhat different standpoint the bricks may be said to be grooved at their opposite sides to conform to and fit against the surface of the tubes 2 between which they are located. 75

A short, semi-cylindrical socket 5 is formed in the upper end of each extension or tongue 4, and extends into the brick for only a short distance, this socket opening on to the grooved face of the brick. A similar socket 6 is formed in the lower end of the extension 4 and at the opposite side of this part of the brick. Short ins 7 are located'in the sockets 5 and 6, as c early shown in Figf, and they serve through their en a ement with the bricks and the tubes to IocIi each brick rml to the two tubes between which it is locate Each brick is thus individually held in its operative osition.

The bricks may e made of any suitable highly refractory lmaterial such as fire clay, silicon carbide or the like, the latter material being referred. The pins also ma be made of si con carbide, or of metal sucr as iron, steel, or the like.

In building a wall of this construction, the bricks 3 may be inserted from the front'or fire face ofthe wall and the pins A7 then placed in the sockets to lock the bricks in position. After the front section or facing of the wall has been completed, then the usual masonry backing, or rear section, may be built immediately behind the tubes. This backing may be of any suitable construction. In some cases such a backing will consist of a brick wall, the bricks being laid in the ordinary manner, but being spaced slightly from the tubes, and a packing of asbestos, magnesia, or the like, will be placed in the space between the tubes and the backing. In some cases, also, a metal shell is located at the rearward side of the backing to assist in making the wall absolutely airtight, as shown for example, in my pending application, Serial No. 286,128 filed June 18, 1928.

W'hen it becomes necessary to make repairs to the wall, it is very desirable to be able to do this work from the fire side of the wall so as to avoid tearing down the rear section of the wall, or that part of it behind the tubes. For this reason I prefer to use key bricks or filler bricks 8, Figs. 1 and 2, at intervals in the vertical rows of bricks 3. It will be seen from an inspection of Fig. 2 that the upper and lower faces of each key brick 8 are vinclined so that this brick is held in its operative position by Gravity, the abutting end of the faces of the lbricks 3 immediately above and below the key brick being correspondingly inclined.

With this construction it is a very simple matter to replace a broken or cracked brick from the fire side to the wall. Assuming, for example, that it is desired to replace the brick 3, Fig. 1, it is simply necessary to remove the key brick 8, which can readily be done from the fire side of the wall, due to the lfact that it is held in the Wall simply by gravity. This brick is of such a height that when it is removed access then is afforded to the pins or locking members 7 the lower locking pin being reached through the space formerly occupied by the key brick, while access is readily obtained to the upper pin 'by allowino the brick 3 to drop. This brick may then be withdrawn at the re side of the wall, a new brick inserted and locked in position by pins 7 and the key brick 8 may then be replaced in its former position.

It will thus-be observed that the invention provides a wall construction which is exceedingly simple, can be manufactured economically, and in which the making of repairs is greatly facilitated. At the same time the bricks are of such construction that they afford ample protection to the tubes. Abundant bearing surface is provided between the bricks and the tubes to permit a rapid transfer of heat from the latter to the former. This construction also lends itself readily to the necessary modifications to accommodate curves and bends in the tubes as will be obvious, the bricks simply being given a curvature corresponding to that of i the tubes. i

Undersome conditions it may be prefer able to provide sockets 5 at both sides of the extension 4 and at both ends thereof. Such a construction is shown in Figs. 5 and 6.

The pins also may be of various cross-sec-V tional forms. Figs. 7 and 8 show a brick 3 of substantially the same form as the brick l3 but held in place by pins 10 which are tapered or wedge shaped in horizontal section, the sockets 11 in which these locking members are located being correspondingly shaped to receive them. Preferably the face of these Wedges 10 are curved where they bear against the tubes 2-2 to conform to the shape of the tubes.. Since these pins, like the pins 7, engage the tubes at the rear of the plane of the tube centers, they cooperate with the portions of the bricks in front of this plane to lock the bricks securely to the tubes. This construction has a further advantage in aording a broad bearing of the locking members or wedges 10 against the tubes.

The area of the tubes which is covered and protected by the bricks will vary somewhat with the practical conditions encountered in individual installations. In some cases, as for example, where the Wall is to be used ingenerating or super heating steam, it may be desirable to expose a considerable portion of the front walls of the tubes to the fire. A brick suitable for this purpose is shown at 3, Fig. 10, the brick otherwise being like that shown in Figs. 7 and 8.

It will also be observed that the extensions 1 of these bricks 3 and 3 are very short so that the rear face of each extension lies approximately in the vertical plane of the rearward sides of the tubes. This is of ad vanta e in saving material and is particularlyesirable in those installations where the rear section of the wall is to be as ppssible to the tubes.

' hile I have herein shown and described preferred embodiments of my invention, it will be understood that the invention may be embodied in a considerable variety of other forms without departing from the spirit or sco e thereof.

y aving thus described my invention what vI claim as new is:

1. In a furnace wall, the combination of a series of substantially parallel tubes, refractory bricks protecting said tubes at the lireside of thewall and each having a portion extending between said tubes, and wedges titting against said tubes and engaging the respective bricks and serving by such engageplaced as close ment to h old the bricks to the tubes, the tapering surfaces of said wedges being disposed transversely to the tubes.

2. In a furnace wall, the combination of a series of substantially parallel tubes, refractory bricks associated with and protecting said tubes at the fire-side of the wall, said bricks having portions lying between adjacent tubes and fitting a ainst the tubes, the tube engaging faces o the bricks having sockets extending into them from the ends of the bricks, and wedges located in said sockets and serving to holdy the bricks to the tubes, said wedges having tapered surfaces disposed transversely to the tubes. v

3. In a furnace wall, he combination of` a series of substantially parallel tubes, refractory bricks associated with said tubes, said bricks being grooved to fit against the tubes, and pins bearlng against the tubes and bricks and serving to lock the bricks to the tubes, the grooved faces of the bricks having sockets open at the end faces of the bricks to receive the pins.

4. In a furnace wall, the combination of a series of substantially parallel tubes, refractory bricks associated with said tubes and each having a part lying between adjacent tubes, and a pin held in said part of each brick adjacent an end face thereof and bearing against one of said tubes and serving to hold the brick to the tube, said pin extending approximately parallel to the tube.

5. In a furnace wall, the combination of a series of substantially parallel tubes, refractory bricks associated with said tubes, each of said bricks having a part protecting the front of a tube and a portion extending between adjacent tubes, said portion being provided adjacent an end face thereof with a socket close beside and .approximately parallel to one of the tubes, and a locking pinl in said socket bearing against said tube and holding the brick to the tube.

6. In a furnace wall, the combination of a series of substantially parallel tubes, refractory bricks associated with said tubes, each of said bricks having a face portion lying in front of two adjacent tubes and a projection extending rearwardly therefrom into the space between said tubes, said projection having sockets adjacent 'end faces of the bricks and close beside and a proximately parallel to said tubes, and loc ing pins in said sockets bearing against said tubes and holding the bricks to the tubes. g

7. In a furnace wall, the combination of a series of substantially parallel tubes, refractory bricks associated with said tubes, and wedges having their tapered surfaces disposed transversely to said tubes, said wedges being shaped to fit against the tubes and operative through engagement with both the tubes and bricks to lock vthe bricks to the tubes.

8. In a furnace wall, the combination of a series of substantially parallel tubes, refractory bricksl bearing against said tubes, each of said bricks having a part protecting the front of a tube and a portion extendlng between adjacent tubes, said portlon being provided with a socket adjacent an end ace thereof and close beside one of the tubes at the rearward side of the tube, and a pin in said socket bearing against and lying parallel'to said tube and holding said brick ,to the tube. 9. InI a furnace wall, the combination of a series of substantially parallell tubes, refractory bricks bearin against said tubes, each of said bricks having a face portion lying in front of two adjacent tubes and a projection extending rearwardly therefrom into the space between said tubes, said projection having sockets extending inwardly from the end faces thereof and located close beside said tubes, and locking pins in said sockets bearing against the rearward sides of said tubes and holding the brick to the tubes.

10. In a furnace wall, the combination of a series of upwardly extending parallel tubes, bricks arranged in rows and having face portions lying in front of said tubes and protecting the tubes at the fire side of the wall and projections extending rearwardly from said face portions and locatedv between adjacent tubes, said bricks being constructed to be placed in or removed from the wall at the re side thereof, key bricks located at intervals in said rows and-held in their o erative positions in the wall by gravity but eing removable from the wall at the fire side thereof, and means for normally locking said bricks other than the key bricks against removal, said means being located adjacent an end face of each of said bricks whereby access thereto is afforded by the removal of the key bricks.

11. In a furnace wall, the combination of a series of upwardly extending parallel tubes,

bricks arranged in rows and having face portions lying in front of said tubes and protecting the tubes at the lire side of the wall and projections extending rearwardly from said face portions and located between adjacent tubes, said bricks being constructed to be placed in or removed from the ywall at the fire side thereof means adjacent an end face of each of said bricks coo erating with said projections to lock the bric s to the tubes, and key bricks located at intervals in said rows and removable from the Wall at the re side thereof, said key bricks being of such dimensions that their removal affords access to the locking means forbricks next adjacent to them. i

12. A brick for furnace wall construction having a roove in one side thereof to fit partly arouncI a tube, and a socket in one end of said brick openin into the grooved face thereof and exten ing for a short distance only into the brick.

OSCAR NYGAARD. 

